Brake



Patented Feb. 12, 193s 1,990,876

UNITED STATES PATENT OFFICE BRAKE v Alvin J. Musselman, Quyahoga Falls,hio

Application March 26, 1931, Serial No. 525,527

4 Claims. (Cl. 18S-152) The invention relates to brakes, and has, amonghub comprises a sleeve 11 which also functions as its other objects, theprovision of improved brakes a brake drum. Mounted on the ends of thesleeve which are durable, eilicient and of simplified con- 11 are anges12 which are adapted to hold a A struction. pneumatic tire (not shown)in place upon the One form of the invention is embodied in a bag sleeve.The sleeve l1 is journaled in ball-bearings 5 which comprises aninternal expanding brake 13 and 14, the ball-bearings 13 and 14 beingband, the brake band being frictionally engagemounted upon a tubulartrunnion 15 which is able with the inner surface of a member which flxedto the framework of the aeroplane (not functions as a brake drum. Theends of the shown). Projecting through the trunnion 15 is l0 brake bandnormally abut against shoulders proa tubular shaft 16 which is also heldagainst ro- 10, vided upon a tubular trunnion which extends into tation.the brake drum, the construction being such that Disposed within thesleeve 1l and frictionally the trunnion holds the brake band againstrotaengageable with the inner surface thereof is an tion while the brakedrum is normally free to rointernal expanding brake band 18 which hasl5y tate. Slidably journaled in the trunnion and also its ends enlarged,aS ndidated at 19. The ends 154 abutting the ends of the brake band area pair of 19 of the brake band normally abut against bars which may bedisplaced to expand the brake shoulders formed upon 'the trunnion 15,the so that it will effectively engage the brake drum construction beingSuch that when both ends 19 and prevent or retard rotation thereof.Disabut against the Shoulder 20. the brake 18 does 20 posed between thebars is a sack or bag which is not effectively engage the inner surfaceof the 20 preferably formed from resilient material, such combined brakedrum and sleeve 11. as rubber, and it is filled with a suitable fluid,Slidably 10111113166. Within a S1015 22 formed in the bag orsack beingconnected to suitable means the drum 15 are bars 23 which also abutagainst whereby the fluid within the bag or s'ack may be the ends 19 ofthe brake drum. As shown, each 25 made to expand the bag to displace thebars. A bar 23 is preferably provided with a bead 24 ex- 25 tube leadinginto one end of the bag or sack contending 10n8itlldina11y thereof, thebead being nects it with the means for causing the fluid to receivedwithin a groove 25 formed in the associexpand the bag or sack, and atube leading out ated end 19.

of the other end of the bag may be utilized to fill A bag 27 disposedWithin the Slot 22 and between 30 the bag and the braking system withthe iluid. the bars 23 is formed from ilexible material. 30

Brakes embodying the invention comprise rel- Thus the bag 27 ispreferably formed from a reatively few parts and the construction issuch silient material, such as rubber. I'he bag isprefthat there is verylittle danger that leaks will erably reotangularincross-section andpreferably develop to render the brakes functionally inopextends fromadjacent one end of the brake band erative. 18 to adjacent the otherend. 35

In the preferred embodiments of the invention, Metallic tubes 28 and 29project from the ends very little clearance is left between vthe surfaceof the bag and are securely xed thereto in such on the brake drum. Thisinsures that the bag manner that fluid tight joints are provided beofresilient material will not be subjected to extween the tubes and thebag. A tube 30 coupled 40 cessive strains or stresses as it is onlynecessary to the outer end of the tube 28 provides means 40 to expand ita very small amount to have the whereby the bag may be operativelyconnected to brake function. any suitable means (not shown) for causingthe Other advantages of the invention will become contents of the bag toexpand it and thus displace 4 apparent as the following detaileddescription the bars 23 away from each other so that they panyingdrawing, wherein: The bag 27 may be filled vwith any suitable Figure 1is a central longitudinal section taken fluid, liquid being preferablyemployed. through the hub portion of an aeroplane wheel, The outer endof the tube 29 is normally closed braking apparatus embodying theinvention bef by a cap 33 but the cap may be removed to bleed ingdisposed within the hub, and the system, or to permit the system to befilled 50 Fig. 2 is a section taken on line 2 2, of Fig. 1. with liquid.Referring to the drawing wherein a preferred The brake is preferably ofthe self-energizembodiment of the invention is illustrated, the ingtype. That is, if the sleeve 11 is rotating reference character 10designates generally the in a clockwise direction (Fig. 2) and the brakehub of an aeroplane wheel. In this instance, the band is expanded, theaction of the sleeve 11 progresses, reference being had to the accomwillexpand the brake band 18. 45

o the brake band is such that the right-hand e d 19 (Fig. 2) will bedriven against the adjacent shoulder 20, and continued rotation o1' thesleeve will tend to expand the band 18 and cause it to more eiectivelyengage the inner surface of the sleeve. Obviously, when the sleeve l1 isrotating in a counter-clockwise direction and the brake band isexpanded, the same action takes place, but in this instance the lefthand end 19 (Fig. 2) is driven into engagement with the shoulder 20associated with it.

While I have shown and described certain embodiments of my invention, itis tc be understood that it is capable of many modifications. Changes,therefore, in the construction and arrangement may be made withoutdeparting from the spirit and scope oi' the invention as disclosed inthe appended claims, in which it is my intention to claim all noveltyinherent in my invention fs broadly as possible, in view of the priorart.

What I claim as new, and desire to secure by Letters Patent, is:

1. The combination with a trunnion member having a slot therethrough, ofa brake drum rotatably mounted thereon, a brake band disposed aroundsaid trunnion member and frictionally engageable with said drum, theends of said brake band registering with said slot, bars slidablyjournaled in said slot and directly engageable with the ends of saidbrake band, and means for displacing said bars relative to each other toforce the brake band into eiective engagement with said brake drum.

2. The combination with a trunnion member having a slot extendingtherethrough, of a brake drum rotatably journaled on said trunnion member, a brake band disposed around said trunnionV member and frictionallyengageable with said brake drum, the ends o! said brake band registeringwith said slot, bars in said slot, said bars being engageable with theends of said brake band and having ilat surfaces slidably engaging thesurfaces of the slot, a flexible bag disposed between said bars, andmeans for connecting said bag to a source o1' uid under pressure.

3. The combination with a hollow trunnion member having a slot extendingthrough its wall, of a brake drum rotatably mounted on said trunnionmember, a brake band disposed around said trunnion member andfrictionally engageable with said brake drum, the ends of said brakeband registering with said slot, means including a ilexible bag disposedin said slot for displacing the ends of the brake band to expand it, anda tube extending through said hollow trunnion member for connecting saidbag with a source o1' fluid under pressure.

4. In combination, a brake drum, a trunnion. anti-friction devicescarried by said trunnion and rotatably journaling said brake drum, saidtrunnion being provided with a slotted enlarged portion intermediate theends oi' said brake drum, a brake band disposed around said trunnionmember and frictionally engageable with said brake drum, the ends ofsaid brake band registering with said slot in said enlarged portion,elongated bars in said slot, said bars being disposed parallel to theaxis of rotation of said brake drum and being engageable with the endsof said brake band, and means disposed in said slot between said barsfor displacing them relative to each other to actuate said brake band.

ALVIN J. MUSSELMAN.

